JP5157305B2 - Wheel position variable vehicle - Google Patents

Description

  The present invention belongs to the technical field of a wheel position variable vehicle capable of changing a wheel position with respect to a vehicle body.

Conventionally, in order to improve vehicle behavior stability, a vehicle-type mobile robot that has multi-joint legs and travels using ordinary tires, or to achieve both vehicle convenience and vehicle behavior stability There are known wheel base variable vehicles and the like (see, for example, Non-Patent Document 1 and Patent Document 1).
Masahiro Toyoda 1 "Target-following control of a vehicle-type robot with redundant articulated mechanism" The Japan Society of Mechanical Engineers No.05-15 Proceedings of the 9th Movement and Vibration Control Symposium 2005.8.23-25 Niigata (http: //www.cl.mes.musashi-tech.ac.jp/abstracts/kawamura.htm) JP-A-2005-231452

  However, the former of the above prior arts has a multi-joint leg, so that the structure is enlarged and complicated, and it is difficult to adapt to an actual vehicle. On the other hand, in the latter case, only the wheelbase is changed, and the convenience of the vehicle is improved, but there is room for improvement in the behavior stability of the vehicle.

  SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a wheel capable of improving the convenience of the vehicle and the stability of the behavior of the vehicle with a simple configuration and realizing a more free vehicle behavior. It is to provide a position variable vehicle.

In order to achieve the above object, the present invention provides:
A suspension device for suspending the wheels;
A steering mechanism provided in the suspension device for changing the direction of the wheel with respect to the vehicle body;
A driving device for driving the wheels;
A wheel position changing mechanism for holding the suspension device movably at an arbitrary position on the track with respect to the vehicle body;
A wheel position control device that outputs to the wheel position changing mechanism a movement command for changing the distance between the wheel in the acceleration direction and the position of the center of gravity in accordance with the direction of acceleration generated in the vehicle body center of gravity;
Equipped with a,
The wheel position changing mechanism includes a track for turning the suspension device in a horizontal direction around one place of the vehicle, and changes the tread base and the wheel base of the vehicle by changing the position of the wheel.
Wheel movement trajectory of the wheel position changing mechanism is characterized trajectory der Rukoto pivoting movement in the horizontal direction all the wheels about the central position of the vehicle body.

In the present invention, since each wheel is moved on the track, the wheel position can be changed with a simple configuration while suppressing energy consumption. Further, more free vehicle behavior can be realized according to the shape of the track.
That is, with a simple configuration, it is possible to improve the convenience of the vehicle and the stability of the behavior of the vehicle, and to realize more free vehicle behavior.

Best Mode for Carrying Out the Invention

  Hereinafter, the best mode for carrying out the present invention will be described based on each example.

First, the configuration will be described.
[overall structure]
FIG. 1 is an external view of a wheel position variable vehicle according to a first embodiment, and two steered wheel units 400 and two drive wheel units 300 are arranged below a vehicle body 100, respectively. Hereinafter, the wheel position change with respect to the vehicle body 100 is referred to as geometry change.

FIG. 2 is a plan view showing the geometry variable vehicle of the first embodiment. The geometry variable vehicle of the first embodiment includes a vehicle body 100, a steering angle sensor 110, an accelerator opening sensor 111, a brake sensor 112, an acceleration & yaw rate sensor ( Acceleration vector detection device) 120, drive wheel unit 300, wheel unit position sensor 310, steering angle sensor 320, drive actuator (drive device) 330, steering actuator (steering mechanism) 340, tread & wheelbase change actuator (wheel) (Position changing mechanism) 350, wheels 390, steering wheel unit 400, and controller (wheel position control device) 500.
The geometry variable vehicle of the first embodiment is a rear wheel drive vehicle in which the steered wheel unit 400 is disposed as the left and right front wheels and the drive wheel unit 300 is disposed as the left and right rear wheels.

The steering angle sensor 110 detects the steering wheel operation amount (steering angle) of the driver. The accelerator opening sensor 111 detects the accelerator operation amount of the driver. The brake sensor 112 detects the amount of brake operation by the driver.
The acceleration & yaw rate sensor 120 detects the acceleration and yaw rate of the vehicle. The wheel unit position sensor 310 detects the positions of the driving wheel units 300 and the steered wheel units 400 on the wheel unit moving track 200.

The turning angle sensor 320 detects the turning angle of the wheel 390 (the wheel turning angle with respect to the front of the vehicle).
The drive actuators 330 are provided in the two drive wheel units 300, respectively, and drive the wheels 390. As the drive actuator 330, for example, an in-wheel motor can be used.
The steered actuator 340 is provided in each drive wheel unit 300 and each steered wheel unit 400, and changes the steered angle of the wheel 390. As the turning actuator 340, for example, an electric motor can be used.

  The tread & wheelbase change actuator 350 moves each drive wheel unit 300 and each steered wheel unit 400 along the wheel unit moving track 200. The tread and wheelbase changing actuator 350 is driven and controlled by the controller 500. In the first embodiment, the wheel unit moving track 200 is set to be a horizontal circle centered on the center of gravity of the vehicle, and each wheel 390 moves on one annular track centered on the center of gravity. The structure for realizing the wheel unit moving track 200 will be described later.

  The controller 500 controls the vehicle speed by driving the drive actuator 330 according to the accelerator pedal opening and the vehicle speed. Further, the steering actuator 340 is driven in accordance with signals from the steering angle sensor 110 and the acceleration & yaw rate sensor 120 to control the traveling direction of the vehicle.

  Further, the controller 500 includes a target tread base, a target tread base according to a running state, a target based on a steering angle sensor 110, an accelerator opening sensor 111, a brake sensor 112, an acceleration & yaw rate sensor 120, a wheel unit position sensor 310, a vehicle body speed, etc. In order to obtain the wheel load of the wheel base and each wheel, the tread & wheel base change actuator 350 is driven to change the position of each wheel.

[Wheel mounting structure]
FIG. 3 is a side view showing a wheel mounting structure in the geometry variable vehicle of the first embodiment.
The wheel 390 is supported by a wheel side support end 600a of a suspension frame (suspension device frame) 600. The vehicle body side support end 600b of the suspension frame 600 is rotatably supported with respect to the vehicle body 100 by a bearing 610 provided on the bottom surface of the vehicle body 100 (or the bottom surface of another suspension frame).

  The suspension arm 650 that suspends the wheel 390 is supported so as to be relatively rotatable with respect to the vehicle body 100 by a linear motor slider (linear slider) 615 provided in an annular shape along the center of the side surface of the vehicle body 100. The linear motor slider 615 according to the first embodiment corresponds to the tread & wheel base changing actuator 350 shown in FIG. 2, and moves the wheel 390 relative to the vehicle body 100 by the thrust in the horizontal direction of the linear motor.

The rod 620 that supports the steered shaft of the wheel 390 has a central portion supported by the suspension frame 600 via the bearing 630 and an upper end portion supported by the suspension arm 650 via the ball joint 640. The suspension arm 650 is provided so as to be rotatable in the vertical direction with respect to the suspension frame 600.
A steering gear 660 is connected to the rod 620, and the wheel 390 is steered by driving a steered actuator 340 fixed to the suspension frame 600.

[Wheel base variable by wheel position movement]
FIG. 4 shows a change state of the wheel base due to the movement of the wheel 390.
As shown in FIG. 4, the geometry variable vehicle of the first embodiment has a minimum of l _a × by moving the wheels using the tread & wheel base changing actuator (wheel position changing mechanism) 350 shown in FIGS. 2 and 3. 2. The wheelbase can be expanded or reduced up to l _c × 2.
Therefore, the geometry variable vehicle according to the first embodiment can reduce the turning radius by reducing the wheel base in extremely low speed driving such as urban driving at a relatively low speed or in a garage, for example. In running and winding, running stability can be obtained by expanding the wheelbase. These operations may be automatically selected according to the vehicle speed or the like, or may be selected by a driver's operation.

  Next, wheel movement control according to the wheel load of the first embodiment will be described. This control is mainly used in normal driving except for the above-described urban driving and garage entry. In other words, in the vehicle according to the first embodiment, in a scene where travel stability is required, not only simply expanding the tread and the wheel base, but also performing wheel movement control according to the wheel load can improve the travel stability. It is intended to improve.

[Effects of wheel load movement on vehicle behavior]
First, FIG. 5 is a diagram showing the influence of wheel load movement on the running behavior of a vehicle. The curve in FIG. 5 is a diagram showing the cornering power Cp with respect to the wheel load load at the time of turning. The solid line shows the cornering power CP of the wheel when wheel load movement occurs during turning with a predetermined vehicle specification. Show. Since the cornering power CP is highly dependent on the tire flatness ratio, the tire flatness ratio 60 (60serise), the tire flatness ratio 70 (70seriese), and the tire flatness ratio 82 (82seriese) are shown respectively. In general, the smaller the tire flatness value, the larger the cornering power, and the larger the tire flatness value, the smaller the cornering power CP, but the fuel efficiency improves.

Looking at the relationship between the cornering power CP with a tire flatness ratio of 70 in FIG. 5 and the wheel load, each wheel load when no turning acceleration occurs is 3.9 kN. For example, when a turning acceleration of 0.3 [G] occurs, The turning outer wheel side increases to 5.5 kN due to wheel load movement, while the inner ring side decreases to 2.3 kN due to wheel load movement. At this time, the cornering power increases due to the increase of the wheel load on the turning outer wheel side, but the cornering power decreases due to the decrease of the wheel load on the turning inner wheel side.
Furthermore, on the turning outer wheel side, the increase in the cornering power accompanying the increase in wheel load tends to increase nonlinearly due to the nonlinearity of the tire lateral force, and the increase in wheel load does not necessarily result in a net increase in cornering power. Is present.

  Therefore, if turning acceleration of 0.3 [G] occurs in a tire with a tire flatness ratio of 70, the total cornering power decreases because the cornering power on the turning inner ring side is larger than the cornering power on the turning outer ring side. Will be. This relationship is indicated by the alternate long and short dash line, and the inner ring side cornering power and outer ring side cornering power that are turning at 0.3 [G] are connected by a straight line, and the wheel load before the start of turning is not moving. When compared with the cornering power at (3.9kN), the decrease in cornering power as shown by the arrow can be confirmed on average.

  Similarly, if the relationship when a turning acceleration of 0.5 [G] occurs in a tire with a tire flatness ratio of 70 is indicated by a thin line, the reduction in the total cornering power becomes more significant. This is especially because the cornering power on the outer ring side has reached a limit value, and the cornering power does not increase even if the wheel load is increased.

  Further, from the graph of the tire flatness ratio 82 and the tire flatness ratio 60, it can be confirmed that the cornering power is decreased due to wheel load movement. This is particularly remarkable when the tire flatness ratio is 82. It can be seen that even in the case of a tire flatness ratio of 60, there is a considerable decrease in cornering power.

  Thus, if there is no movement of the wheel load accompanying turning, the cornering power does not decrease and the turning performance does not deteriorate and the vehicle behavior can be stabilized. Even when it is not necessary to increase the maximum value of the cornering power, it is possible to select a tire with a high flatness ratio, so that an improvement in fuel consumption can be expected.

  In other words, if the wheel load can be evenly distributed when turning, the wheel load will not move, the tires of each wheel 390 can be used evenly, the cornering power will not decrease, and the vehicle behavior will be stable It becomes possible to make it.

Although the influence on the cornering power is shown in FIG. 5, the same tendency can be seen even if the cornering power is replaced with the deceleration G and the acceleration G. That is, when the wheel load moves due to acceleration / deceleration, the tire friction force on the side where the wheel load has increased reaches the limit, and the braking force and acceleration force are limited. On the other hand, although the tire on the side where the wheel load is reduced has a margin in the tire friction force, the tire friction force cannot be transmitted to the road surface because the wheel load is reduced.
Therefore, if the wheel load can be evenly distributed during deceleration and acceleration, the vehicle behavior can be stabilized.

[Wheel load distribution control]
Next, FIG. 6 shows the positions of the tread base and the wheel base when the wheel loads of the four wheels are equally distributed. In Example 1, each wheel position is changed so that the wheel loads of the four wheels are equal. 6A shows the relationship between the wheel position when the vehicle is viewed from above and the center of gravity of the vehicle, and FIG. 6B is the wheel position when the vehicle is viewed from the side perpendicular to the acceleration direction. And the position of the center of gravity.

In FIG. 6 (a), when the combined acceleration (yaw rate, centrifugal force for turning, front / rear G for acceleration / deceleration, or both) occurs due to wheel steering, acceleration / deceleration, etc. The acting acceleration in the plane direction is expressed as a combined acceleration G _{(x, y)} . Further, the direction in which the resultant acceleration G _{(x, y)} is generated is set as the resultant acceleration direction axis CA _(h) .
Then, the axis perpendicular to the combined acceleration direction axis CA _(h) and the plane direction at the center of gravity G of the vehicle body is set as the combined acceleration direction orthogonal axis CA _(p) .

Here, the resultant acceleration vector G _{(x, y)} is obtained by the acceleration & yaw rate sensor 120 attached to the vehicle body 100, and the X direction and the Y direction are determined based on the attachment position and direction of the sensor 120 with respect to the vehicle body 100, Generally, the longitudinal direction of the vehicle body 100 is set to the X direction, and the lateral direction of the vehicle body 100 is set to the Y direction.

ここで、
G_(x,y)={(G_(x)+ΔG_(x))²+(G_(y)+ΔG_(y))²}^1/2：合成加速度
G_(i)：加速度&ヨーレートセンサから検出
ΔG_(i)：目標車両姿勢から算出された姿勢補正加速度
ｍ：車両質量
h：重心高さ
G_(z)：重力加速度
である。 Next, the axis obtained by translating the composite acceleration direction perpendicular axis CA _(p) to the composite acceleration vector direction G _{(x, y)} by l ₂ and l _{1 in the} opposite direction to the composite acceleration vector direction G _{(x, y)} , respectively. The virtual axle is an acceleration rear axis and an acceleration front axis.
Further, if the vertical acceleration (mainly gravitational acceleration) acting on the vehicle body center of gravity G is a vector G _(z) and the height of the center of gravity from the road surface is h, the acceleration rear axis, acceleration front described above The acceleration rear axle wheel load W ₂ and the acceleration front axle wheel load W ₁ acting on the shaft are expressed by the following equation (1).

here,
G _{(x, y)} = {(G _(x) + ΔG _(x) ) ² + (G _(y) + ΔG _(y) ) ² } ^1/2 : Composite acceleration
G _(i) : Detected from acceleration & yaw rate sensor ΔG _(i) : Posture correction acceleration calculated from target vehicle posture m: Vehicle mass
h: Height of the center of gravity
G _(z) : Gravitational acceleration.

According to the equation (1), in order to suppress the wheel load movement and stabilize the vehicle behavior, the wheel load W _{2 on} the acceleration rear axis and the wheel load W _{1 on the} acceleration front shaft need only be equalized. In 1), W ₁ ≈W ₂ should be satisfied. As is clear from Equation (1), if l ₁ and l ₂ are infinite, W ₁ ≈W ₂ regardless of the magnitude of G _{(x, y)} . This indicates that the wider the distance between the wheels, the smaller the wheel load movement amount due to the combined acceleration and the more stable the vehicle behavior, which corresponds to a generally known wide tread base and long wheel base.

  In the conventionally proposed variable geometry vehicle, when both a compact vehicle and a vehicle with stable vehicle behavior are compatible, a vehicle with a wide tread base and a long wheel base is used in high vehicle speed ranges (high speed running and winding) where large acceleration occurs. In a low vehicle speed range (for example, an urban area) where the behavior is stabilized and a large acceleration does not occur, a narrow tread base and a short wheel base are used to increase the compactness and small turning ability.

ここで、
G_rate=G_(x,y)/G_z：加速度比
l_rate=l₁/l₂：ジオメトリ比
h_rate=h/l₂：高さ比
である。 However, in view of the direction of the combined acceleration, it can be seen that the movement of the wheel load can be suppressed even if it is not necessarily the wide tread base or the long wheel base.
That is, in order to equalize the wheel loads of the four wheels, W ₁ = W ₂ , that is, l ₁ and l ₂ may be set so as to satisfy the following expression (2).

here,
G _rate = G _{(x, y)} / G _z : Acceleration ratio
l _rate = l ₁ / l ₂ : Geometry ratio
h _rate = h / l ₂ : Height ratio.

According to Equation (2), when the resultant acceleration G _{(x, y)} is generated in a certain direction, the two virtual axle positions for equally distributing the wheel loads of the four wheels are obtained. If four wheels are arranged so as to realize, the wheel load distribution of the four wheels becomes equal.

The wheel loads on the left and right wheels with respect to the virtual spindle are caused by W ₁ and W ₂ as shown in FIGS. 6 (c) and 6 (d), but the movement trajectory is true as in this embodiment. In the circular shape, both wheels are always equidistant from the load point on the virtual axle simply by arranging the wheels on the virtual axis, so calculation of wheel load distribution to the left and right wheels relative to the virtual axle can be omitted.

FIG. 7 shows the movable range of l ₁ and l ₂ when the axle loads of W ₁ and W ₂ are evenly distributed.
Figure 7 is obtained by calculating the l _1, the movable range of l ₂ when the center of gravity height h and _{0.5 [m], l 1,} l 2 of the axle load and evenly to the plane acceleration [G] A plot of these combinations is represented as a wheel load uniform surface α.

Based on Fig. 7, considering that the wheel load of four wheels is equally distributed with the minimum distance between the axes, the general vehicle acceleration G _rate is the maximum value, 1.1 [G] (friction coefficient of about 1.0, special Even if the down force does not exist), the movable range of l ₁ and l ₂ in which the wheel load can be evenly distributed is searched from the graph shown in FIG.

As shown by the line min in FIG. 7, when l ₁ = 0, l ₂ = 1.1 [m], the wheel load is evenly distributed at the point E at the maximum acceleration with l ₁ and l ₂ at the minimum movable range. be able to. In other words, if the vehicle can change l ₁ from 0 to 1.1 [m] and l ₂ from 0 to 1.1 [m], the wheel load is evenly distributed regardless of the G _rate of 1.1 [G]. be able to.

[Wheel movement control]
As described above, in the vehicle in which l ₁ can be varied between 0 and 1.1 [m] and l ₂ between 0 and 1.1 [m], the wheel load equal distribution control will be further described with reference to FIG.

For example, assume that the initial position of the wheel is 0.8 [m] for l ₁ and 0.8 [m] for l ₂ . This is point A in FIG. When the vehicle travels without acceleration, deceleration, or turning, the vehicle is positioned on the uniform distribution plane α because of acceleration 0 [G].

Next, when the turning acceleration is 0.2 [G], the position of the wheel is changed so that the point B is obtained. If there is no intersection on the uniform distribution plane in FIG. 7, the uniform distribution of the wheel load distribution cannot be realized, and therefore l ₁ and l ₂ satisfying the uniform distribution of the wheel load when the acceleration is 0.2 [G] are searched.
At this time, in the first embodiment, the wheel positions are searched such that the movement amounts of the wheels 390 are equal. That is, the point B is Δl ₁ = −0.1 and Δl ₂ = + 0.1, the point B ′ is Δl ₁ = −0.2 and Δl ₂ = 0, and the total movement amount is the same. The total movement distance of the actuator movement distance is the sum of the movement distances of the four actuators in the case of point B, and can be shared by the four actuators. The move can be completed faster. In this way, the point moves to point D according to the increase in acceleration. And when acceleration further increases, it moves toward the point F.
It should be noted that from point D to point F, only l ₁ changes and the actuator sharing is not equalized, but it is set in view of the frequency of acceleration of 0.6 [G] or more.

  As described above, the equal distribution of the wheel load can be realized with a short distance between the axles, and the decrease in cornering power can be suppressed by performing the equal distribution of the wheel load. That is, even a compact vehicle can improve vehicle behavior such as turning behavior while maintaining a compact vehicle geometry by moving the tire unit.

Next, the effect will be described.
The geometry variable vehicle according to the first embodiment has the following effects.

  (1) A suspension device (rod 620, bearing 630, ball joint 640, suspension arm 650) for suspending the wheel 390, a steering actuator 340 provided on the suspension device for changing the direction of the vehicle body 100, and the wheel 390 are driven. Drive actuator 330, a tread and wheelbase change actuator 350 that holds the suspension device movably on the track (wheel unit moving track 200) with respect to the vehicle body 100, and the direction of acceleration generated at the center of gravity of the vehicle body And a controller 500 that outputs to the tread & wheelbase change actuator 350 a command to change the distance between the wheel 390 and the center of gravity position in the acceleration direction. As a result, it is possible to realize a compact and high traveling stability vehicle with a simple configuration while suppressing energy consumption.

  (2) The tread & wheelbase changing actuator 350 includes a track (wheel unit moving track 200) for turning the suspension device horizontally around one place of the wheel 390, and the vehicle tread base is changed by changing the position of the wheel 390. And change the wheelbase. Thereby, a tread base and a wheel base can be changed, maintaining a fixed relationship.

  (3) Since the wheel movement trajectory of the tread & wheel base change actuator 350 is a trajectory in which all the wheels 390 turn in the horizontal direction around the center position of the vehicle body 100, the tread base and the wheel base have a certain relationship. Can be changed while maintaining

(4) The wheel movement trajectory of the tread & wheelbase change actuator 350 is a trajectory in which all the wheels 390 turn in the horizontal direction around the center position of the vehicle body 100 without changing the distance between the center position and the wheels 390. Thus, one annular track is formed. In other words, since the two circular wheels arranged on the virtual axle can be arranged at the same distance from the resultant acceleration G _{(x, y)} by using the circular circular track, the two wheels arranged on the axle are provided. Also, the load distribution becomes uniform, and control can be facilitated.

  (5) An acceleration & yaw rate sensor 120 that detects the acceleration vector of the vehicle in the horizontal plane is provided, and the controller 500 changes the position of each wheel based on the direction of the detected acceleration vector. Thereby, the control direction becomes one direction, and control can be facilitated.

(6) The controller 500 bisects each wheel 390 around the right axis of the acceleration vector, and changes each wheel position based on the right axis and the distance to each wheel 390. In other words, the wheelbase (front axis to center of gravity distance l ₂ , center of gravity to rear axis distance l _{1 in} the opposite direction) is set from the balance of the left and right forces across the right-angle axis. It can be made easier.

  (7) The controller 500 sets the distance from the wheel on the acceleration direction side to the center of gravity position to be longer than the distance from the wheel on the opposite side to the acceleration direction to the position of the center of gravity. That is, since the wheel positions are changed so that the wheel loads of the wheels 390 are equal, the turning behavior of the vehicle can be improved.

  (8) The tread & wheelbase change actuator 350 is supported on the vehicle body side opposite to the suspension frame 600 that supports the suspension device (suspension arm 650) and the wheel side support end 600a that supports the suspension device of the suspension frame 600. A bearing 610 that rotatably supports the end 600b on the vehicle body 100, and an actuator (linear motor slider 615) that is provided between the suspension frame 600 and the vehicle body 100 to move the vehicle body 100 and the suspension device relatively. . Thereby, the wheel position changing mechanism that holds the suspension device movably to an arbitrary position on the track with respect to the vehicle body 100 can be realized with a simple configuration.

  (9) Since the actuator is the linear motor / slider 615 provided in an annular shape on the vehicle body 100, an actuator for relatively moving the vehicle body 100 and the suspension device can be realized with a simple configuration.

The second embodiment is an example in which the wheel position is changed based on a wheel load distribution target corresponding to the traveling state. In the case of the first embodiment, the wheel load is uniformly distributed, but in this embodiment, the wheel load is non-uniformly distributed according to the situation.
Since the configuration of the second embodiment is the same as that of the first embodiment except for [Wheel load equal distribution control], the illustration and description are omitted.

[Random load distribution control]
FIG. 8 shows the positions of the tread base and the wheel base in the case of arbitrarily distributing the wheel loads of the four wheels. Specifically, the control for distributing the wheel loads so that the wheel loads on the drive wheels are increased. Is shown.

  In the first embodiment, an example is shown in which wheel loads are equally distributed for the purpose of evenly using four tires. Here, when the function of each wheel such as braking and turning is the same, it was possible to stabilize the vehicle behavior by equally distributing the wheel load, but the function of each wheel 390 such as the driving wheel and the driven wheel is In different cases, evenly distributed wheel loads do not necessarily lead to stable vehicle behavior.

  For example, when accelerating, a large driving force can be transmitted to the road surface by increasing the wheel load of the driving wheel, but the driving force cannot be transmitted even if the wheel load of the driven wheel is increased. In other words, at the time of acceleration, it is preferable to increase the wheel load of the driving wheel within a range that does not impair the friction limit of the tire and the straightness of the vehicle. Especially in the acceleration scene of a rear-wheel drive vehicle, trying to distribute the wheel load evenly acts to return the wheel load moved to the rear wheel side to the front wheel side, so the wheel load on the rear wheel side increases. Without doing so, the acceleration performance could be deteriorated.

Also in the second embodiment, as in the first embodiment, a vector perpendicular to the vector G _{(x, y)} based on the direction of the resultant acceleration vector G _{(x, y)} of acceleration in any two directions on the plane motion. Centering on the vector axis of G _(z), the distance between the front axis and the center of gravity l ₂ is set in the same direction as the combined vector G _{(x, y),} and the center of gravity and the rear axis distance l ₁ are set in the opposite direction.

ここで、
W_rate= W₁ / W₂：輪荷重比 In the second embodiment, the formula (2) used in the first embodiment is changed as follows.

here,
W _rate = W ₁ / W ₂ : Wheel load ratio

According to Equation (3), when the resultant acceleration G _{(x, y)} occurs in a certain direction, the two virtual axle positions when the wheel loads of the four wheels are equally distributed are obtained, and the obtained virtual axle is If four wheels are arranged to realize, the wheel load ratio of the virtual axle becomes W _rate .

That is, the controller 500 sets W _rate to an arbitrary value (0 to 1) when the driving wheel 300 is in an accelerating state and the direction of acceleration is the longitudinal direction of the vehicle body.
Further, by setting W _rate = 1 during turning and braking, the wheel load can be equally distributed as in the first embodiment.
In addition, since [Wheel movement control] of the second embodiment is the same as that of the first embodiment, the description thereof is omitted.

Next, the effect will be described.
In addition to the effects (1) to (9) of the first embodiment, the geometry variable vehicle of the second embodiment has the following effects.

  (10) Since the controller 500 makes the wheel load of the drive wheel larger than the wheel load of the steered wheel, the drive wheel slip during acceleration can be suppressed and the acceleration performance of the vehicle can be improved.

The third embodiment is an example in which the wheel position is changed based on the target vehicle posture.
In addition, about the structure of Example 3, since it is the same as that of Example 1 and Example 2 other than [Wheel load equal distribution control] of Example 1, and [Wheel load arbitrary distribution control] of Example 2, it is the same. Illustration and description are omitted.

[Target vehicle attitude control]
FIG. 9 shows the positions of the tread base and the wheel base when the wheel loads of the four wheels are arbitrarily distributed. In the third embodiment, the wheel loads are changed based on the target vehicle posture.

Also in the third embodiment, as in the first embodiment, a vector perpendicular to the vector G _{(x, y)} with reference to the direction of the combined acceleration vector G _{(x, y)} of acceleration in any two directions on the plane motion. Centering on the vector axis of G _(z), the distance between the front axis and the center of gravity l ₂ is set in the same direction as the combined vector G _{(x, y),} and the center of gravity and the rear axis distance l ₁ are set in the opposite direction.

ここで、
ｋ：車輪と車体間のバネ係数（主としてサスペンションバネ係数） When the posture angle in the acceleration direction is tan θ, tan θ is expressed by the following equation (4).

here,
k: Spring coefficient between wheel and vehicle body (mainly suspension spring coefficient)

According to the equation (4), it can be understood that the attitude angle of the vehicle can be controlled by setting W ₁ and W ₂ to arbitrary values when the resultant acceleration G _{(x, y)} occurs in a certain direction.
As described in the first embodiment, if the wheel load is controlled to be equally distributed, W ₁ = W ₂ , so that the attitude angle is 0 °, and the state is always flat.
On the other hand, if the wheel load is arbitrarily distributed as in the second embodiment, a desired posture angle can be obtained.

In the third embodiment, l ₁ and l ₂ are set so as to satisfy the posture correction acceleration ΔG _(i) calculated from the target vehicle posture based on the roll angle and the pitching angle. As a result, the desired vehicle posture can be obtained, and the vehicle behavior is stabilized by suppressing rolling during rough turns and crosswinds, bumpy roads, sudden starts, and pitching phenomena (nose dives, squats) during sudden braking. Can be achieved.

Next, the effect will be described.
The geometry variable vehicle of the third embodiment has the following effects in addition to the effects (1) to (6), (8), and (9) of the first embodiment.

  (11) Since the controller 500 changes the position of each wheel 390 based on the target wheel load of each wheel 390 calculated from the target vehicle attitude, a desired target vehicle attitude can be obtained according to the traveling state. .

  (12) Since the controller 500 sets the target vehicle attitude based on the roll angle of the vehicle, the roll angle can be set freely. Therefore, for example, it is possible to suppress an increase in the roll angle when turning or receiving a crosswind, and to stabilize the vehicle behavior.

  (13) Since the controller 500 sets the target vehicle attitude based on the pitching angle of the vehicle, the pitching angle can be set freely. Therefore, for example, a squat when suddenly starting, a nose dive during sudden braking, and the like can be suppressed.

The fourth embodiment is an example in which a wheel serving as a base point is set in accordance with the direction of acceleration and a wheel position other than the base point is moved.
Since the configuration of the fourth embodiment is the same as that of the first embodiment except for [wheel movement control], the illustration and description thereof are omitted.

[Wheel movement control]
In the first embodiment, the wheel movement position is calculated so that the movement distances of the respective wheels 390 are equal, but in the third embodiment, one axle distance is fixed and the other axle distance is varied. Yes. Specifically, when the acceleration direction of the axle distance was l _2, as opposite l ₁ and the acceleration direction, the axle distance is variable has only l _1.
FIG. 10 shows the movable ranges of l ₁ and l ₂ when the axle loads of W ₁ and W ₂ are equally distributed as in the uniform distribution surface shown in the first embodiment.

As in the first embodiment, assume that l ₁ is 0.8 [m] and l ₂ is 0.8 [m] with the initial wheel position as the initial position A. At this time, when l ₂ is a fixed value, up to about 0.8 [G], as shown in the movement from the point A to the point B, the wheel load even distribution can be performed only by varying l ₁ . The following driving scene is assumed using such an action.

  FIG. 11 is a diagram illustrating the wheel arrangement at the time of acceleration. In Example 4, each wheel position is set such that the wheel base is longer than the tread base during constant speed travel in which the vehicle does not generate acceleration. At the time of acceleration, the rear wheel is used as a base point, and only the front wheel is moved to the vehicle rear side to obtain a desired vehicle posture. In other words, during vehicle acceleration, the wheel load on the front wheel decreases and the wheel load on the rear wheel increases, so by moving only the front wheel with a small wheel load, the load on the tread & wheelbase change actuator 350 is reduced. Control responsiveness can be improved. In addition, by moving the front wheels to the rear side of the vehicle, the center of gravity moves to the rear side of the vehicle as the vehicle accelerates. On the other hand, changes in the wheel load of each wheel can be suppressed, and the vehicle behavior during acceleration is stabilized. be able to.

  FIG. 12 is a diagram showing the wheel arrangement at the time of deceleration, and at the time of deceleration, the front wheels are used as base points and only the rear wheels are moved to the vehicle front side to obtain a desired vehicle posture. That is, when the vehicle decelerates, the wheel load on the front wheel increases and the wheel load on the rear wheel decreases, so only the rear wheel with a small wheel load is moved to reduce the load on the tread & wheel base change actuator 350. At the same time, control responsiveness can be enhanced. In addition, by moving the rear wheel to the front side of the vehicle, the center of gravity moves to the front side of the vehicle as the vehicle decelerates, while the wheel load change of each wheel can be suppressed, and the vehicle behavior during deceleration is stable. Can be made.

  FIG. 13 is a diagram showing the wheel arrangement at the time of turning. At the time of turning, the turning outer wheel is used as a base point, and only the turning inner wheel is moved to the axle (vehicle center) side to obtain a desired vehicle posture. That is, when the vehicle is turning, the wheel load of the inner turning wheel decreases and the wheel load of the outer turning wheel increases. Therefore, by moving only the turning inner wheel, the load on the tread & wheelbase change actuator 350 is reduced and control is performed. Responsiveness can be improved. In addition, by moving the turning inner wheel toward the axle, the center of gravity moves to the outside of the turning as it turns, whereas the wheel load change of each wheel can be suppressed and the vehicle behavior during turning can be stabilized. Can do.

  FIG. 14 is a diagram showing the wheel arrangement at the time of decelerating turning, and at the time of decelerating turning, the front wheel on the turning outer wheel side closest to the center of gravity moving direction is used as a base point, and the other three wheels are moved in a direction to suppress the wheel load change. To obtain a desired vehicle posture. In other words, the wheel load on the front wheel on the turning outer wheel side among the four wheels becomes the largest during deceleration turning of the vehicle, so the tread and wheelbase can be changed by moving the other three wheels from the front wheel on the turning outer wheel side. The load on the actuator 350 can be reduced and the control response can be improved.

  FIG. 15 shows a reduced state of the actuator load. FIG. 15 shows a state in which a turn G is gradually generated after the start of turning, in which the bold line is the present embodiment, the alternate long and short dash line is the state of the first embodiment, and the thin line is the wheel load control. This is an example that is not implemented.

  Here, assuming that t0 is in a state where no turning acceleration occurs, a load load-m corresponding to the vehicle weight is applied. When control is performed so that the wheel load is always kept uniform as in the first embodiment when the turning is started, the actuator always requires the actuator driving force load-A corresponding to the load load-m. It can be seen that when the actuator is driven after the turning G has occurred and the wheel load movement has occurred as in the embodiment, a small actuator driving force load-B is required.

  However, according to this embodiment, in order to finally equalize the wheel load, the actuator driving force load-A is required as in the first embodiment, but it is necessary to completely equalize the wheel load. There are very few scenes, and even if some non-uniformity in wheel load occurs, the friction limit on the outer ring side is not exceeded, so that the actuator driving force required in most driving scenes can be reduced.

  As shown in FIG. 15, in order to move the wheel in a state where the wheel load on the outer ring side is increased, a larger actuator driving force load-C is required. If G can be predicted, or if an increase in turning G is predicted from the driving state, the wheel movement control is stopped before the inner wheel position reaches the movement width limit, and the wheel load is evenly distributed by the actuator thrust load-A. By quickly moving the inner ring wheel to the position, even if the turning G increases, both the inner and outer wheels may be moved with the actuator thrust load-A thereafter. In this case, the maximum driving force of the actuator may be about Load-A.

Next, the effect will be described.
The geometry variable vehicle of the fourth embodiment has the following effects in addition to the effects (1) to (5), (8), and (9) of the first embodiment.

  (14) Since the controller 500 changes the position of each wheel in a direction in which the wheel load change of each wheel is further reduced, the vehicle behavior can be stabilized.

  (15) When changing the position of each wheel, the controller 500 sets one wheel position as a base point, and changes the wheel position other than the base point. As a result, the control can be facilitated.

  (16) Since the controller 500 sets a wheel having a larger wheel load than the wheel whose wheel position is changed as a base point, the control responsiveness can be improved and the energy required for moving the wheel can be kept small. .

  (17) Since the controller 500 sets the wheel closest to the center-of-gravity movement direction as a base point, the control responsiveness can be improved and the energy required to move the wheel can be kept small.

The fifth embodiment is an example in which the moving trajectory of the wheel is displaced not only in the horizontal direction but also in the vertical direction of the vehicle.
FIG. 16 is a diagram illustrating a geometry variable vehicle according to the fifth embodiment. In the fifth embodiment, the wheel unit moving track 200 is curved in the vehicle vertical direction. Thereby, when each wheel position is changed, not only the wheel position but also the vehicle height can be changed simultaneously.

  The structure for changing the wheel position and the vehicle height at the same time will be specifically described in Example 6 described later. In Example 5, each wheel unit is placed on a rail provided on the vehicle body 100 (on the wheel unit moving track 200). Since the vehicle height can be changed by moving 300,400, the rail shape will be described here.

  As shown in FIG. 16 (a), when viewed from the top of the vehicle, the moving track of each wheel 390 is on one annular track (wheel unit moving track 200) centered on the center of gravity as in the first to fourth embodiments. Will be moved. On the other hand, when the vehicle is viewed from the side as shown in FIG. 16 (b), both ends of the moving track are not horizontal but both ends are displaced upward. Furthermore, as shown in FIG. 16 (c), when viewed from the rear (or front) of the vehicle, both ends of the moving track are not horizontal but both ends are displaced downward.

FIGS. 17A to 17C and FIGS. 19A to 19C show changes in the center of gravity when the wheel unit 400 (or 300) moves on the vehicle movement track shown in FIG.
As shown in FIG. 17, in the wheel movement trajectory, when each wheel 390 moves from the reference position in the direction of arrow B in the tread base reduction-wheel base extension direction, the vehicle lowers the position of the center of gravity. On the other hand, as shown in FIG. 18, when one wheel unit moves in the tread base reduction direction in the direction of arrow B-moving in the wheel base expansion direction, the center of gravity is lowered, and the other moves in the tread base extension in the direction of arrow A- Then, the center of gravity does not change and the vehicle body 100 tilts.

Thus, a suitable example in the case where the moving track of the wheel 390 is displaced not only in the horizontal direction but also in the vertical direction of the vehicle is shown as two wheel moving tracks in FIGS.
FIG. 19 shows an example in which the rail shape (wheel unit moving track 200) is set so as to lower the position of the center of gravity when moving in the direction of expansion of the tread base in the direction of arrow A to the direction of contraction of the wheel base. Base reduction—Wheel 390 is moving in the direction of lowering the center of gravity when moving in the wheel base expansion direction.
Even if the left and right wheel units move in different directions of the A direction and the B direction as shown in FIG. 19 (a), the center of gravity of the vehicle falls, and the left and right wheel units move in the B direction as shown in FIG. 19 (b). However, even if the left and right wheel units move in the direction A as shown in FIG.

  According to such a configuration, when the wheel position is moved, the position of the center of gravity is always lowered. Therefore, h (center of gravity height) in the expression (1) described in the first embodiment becomes a small value, and the wheel position The effect due to movement appears remarkably. That is, it is possible to perform the wheel load distribution control of the first embodiment even with a small wheel movement amount.

  However, in the rail shape of FIG. 19, when all the wheels move by the same amount as in the first embodiment, the center of gravity of each wheel 390 has the same height, which is preferable. Thus, when performing wheel movement based on the wheel to which a load is applied, the vehicle height of the moved wheel and the wheel serving as the base point may be different from each other.

  Therefore, as shown in FIG. 20 (FIG. 17 is also the same), the center of gravity position is set so that the wheel movement trajectory does not change when moving in the tread base expansion direction to the wheel base reduction direction in the arrow A direction. Tread base reduction-It is conceivable to set the wheel movement trajectory so as to lower the position of the center of gravity when moving in the wheel base extension direction.

  As shown in FIG. 20 (a), when the left and right wheel units are moved in different directions of the A direction and the B direction, the center of gravity is lowered by the movement in the B direction, but the center of gravity is not changed by the movement in the A direction. Inclined as. Further, when the left and right wheel units move in the B direction as shown in FIG. 19 (b), the center of gravity of the vehicle decreases, and when the left and right wheel units move in the A direction as shown in FIG. 19 (c), the center of gravity changes. do not do.

  According to the wheel movement trajectory shown in FIG. 20, for example, at the time of acceleration shown in FIG. 11 of the fourth embodiment, the center of gravity does not change even if the wheel 390 is moved. There is no effect. The same applies to the deceleration of the vehicle shown in FIG.

  On the other hand, at the time of turning as shown in FIG. 13, the vehicle height on the inner ring side which is a moving wheel is lowered, so that a so-called reverse roll state is obtained, and the vehicle behavior becomes a more stable direction. Therefore, the wheel movement amount can be reduced. Here, when there is a change in the center of gravity due to movement in the direction A in FIGS. 11 and 12, the movement of the center of gravity due to the inclination of the vehicle acts in the direction of worsening the distribution, which is not preferable. That is, when the wheel movement is performed with the loaded wheel as a base point, the wheel movement trajectory shown in FIG. 20 is suitable.

  Which of the wheel movement trajectories shown in FIG. 19 and FIG. 20 is selected may be appropriately selected according to the ability of the wheel movement actuator and the required vehicle performance. For example, the wheel movement actuator is powerful and the required vehicle performance is high. In this case, it is possible to provide a vehicle with high performance by selecting the wheel movement trajectory of FIG. 19 and executing the control of the first embodiment. When the required vehicle performance is not so high, select the wheel movement trajectory of FIG. By executing the control of the fourth embodiment, it is possible to provide a lower cost vehicle.

In addition to the rail, the method of raising and lowering the wheel movement trajectory is such that the arm itself moves up and down according to the screw or ball screw according to the rotation at the position where the wheel unit is attached to the vehicle body 100, the one using a cam, By using the one with the attachment shaft attached obliquely, the wheel movement trajectory can be moved up and down in accordance with the movement of the wheel unit.
The amount of movement up and down the movement trajectory can also be set arbitrarily.

Next, the effect will be described.
In the geometry variable vehicle of the fifth embodiment, the effects (1) to (9) of the first embodiment, the effects (10) of the second embodiment, the effects (11) to (13) of the third embodiment, and the fourth embodiment. In addition to the effects (14) to (17), the following effects are achieved.

  (18) The wheel movement trajectory of the tread & wheelbase change actuator 350 is a trajectory in which all the wheels 390 turn in the horizontal direction around one place of the vehicle. The trajectory is displaced in the direction. For this reason, when changing the wheel position, the vehicle height can be adjusted simultaneously with the adjustment of the tread base and the wheel base, so that the vehicle attitude control with a higher degree of freedom can be realized and the vehicle behavior can be further improved. .

FIG. 21 is a side view showing a wheel mounting structure in the geometry variable vehicle of the sixth embodiment.
In the sixth embodiment, a suspension frame (suspension device frame) 600 includes a slider (rail) 670 that is annularly provided along the lower side of the vehicle body 100 and a linear that is annularly provided along the center of the side surface of the vehicle body 100. A motor / slider (actuator) 615 is supported so as to be rotatable relative to the vehicle body 100.
The other configuration is the same as that of the first embodiment shown in FIG.

  Next, the operation will be described. In the sixth embodiment, since the suspension frame 600 is supported by the side surface of the vehicle body 100, the vehicle body 100 is lower than the configuration of the first embodiment in which the suspension frame is supported by the bottom surface of the vehicle body. The center of gravity can be set lower.

Next, the effect will be described.
In addition to the effects (1) to (7) and (9) of the first embodiment, the geometry variable vehicle of the sixth embodiment has the following effects.

  (19) The tread & wheelbase changing actuator 350 is provided around the vehicle body and the suspension frame 600 that supports the suspension device (rod 620, bearing 630, ball joint 640, suspension arm 650). A slider 670 supported by the vehicle body 100 and an actuator (linear motor / slider 615) provided between the suspension frame 600 and the vehicle body 100 for moving the vehicle body 100 and the suspension device relative to each other are provided. As a result, the height of the center of gravity can be set lower than in the first embodiment, and the running stability can be further increased.

FIG. 22 is a side view showing a wheel mounting structure in the geometry variable vehicle of the seventh embodiment.
In the seventh embodiment, the wheel 390 is supported by a wheel side support end 680a of a trailing type suspension frame (suspension device frame) 680. The vehicle body side support end 680b of the suspension frame 680 is rotatably supported with respect to the vehicle body 100 by a bearing 610 provided on the bottom surface of the vehicle body 100 (or the bottom surface of another suspension frame).

  The wheel side support end 680a of the suspension frame 680 is supported so as to be rotatable relative to the vehicle body 100 by a linear motor / slider (actuator) 615 provided in an annular shape along the center of the side surface of the vehicle body 100. In the suspension frame 680, the wheel side support end 680a and the vehicle body side support end 680b are connected by a hinge portion 680c. For this reason, the wheel side support end (foldable portion) 680a can swing in the vertical direction with respect to the vehicle body side support end 680b.

Between the linear motor / slider 615 and the wheel side support end 680a of the suspension frame 680, a shock absorber 690 for absorbing vibration input to the wheel 390 from the road surface is interposed.
The other configuration is the same as that of the first embodiment shown in FIG.

  Next, the operation will be described. In the seventh embodiment, for example, when traveling on a rough road, the wheel side support end 680a of the suspension frame 680 swings in the vehicle vertical direction with respect to the road surface input to the wheel 390, and the shock absorber 690 Is absorbed by. For this reason, it is possible to suppress the input from the road surface from being transmitted to the vehicle body 100 side.

Next, the effect will be described.
In addition to the effects (1) to (7) and (9) of the first embodiment, the geometry variable vehicle of the seventh embodiment has the following effects.

  (20) The tread & wheelbase change actuator 350 is composed of a suspension frame 680 that supports the suspension device (rod 620, bearing 630), and a vehicle body on the opposite side of the wheel side support end 680a that supports the suspension device of the suspension frame 680. A bearing 610 that rotatably supports the side support end 680b with respect to the vehicle body 100, and an actuator (linear motor slider) that is provided between the suspension frame 680 and the vehicle body 100 and relatively moves the vehicle body 100 and the suspension device. 615), and the suspension frame 680 includes a retractable portion (wheel-side support end 680a) that can be tilted according to the force from the road surface input to the wheel 390. As a result, it is possible to provide a comfortable driving environment with good riding comfort.

FIG. 23 is a side view showing a wheel mounting structure in the geometry variable vehicle of the eighth embodiment.
The eighth embodiment is an example in which a double wishbone type suspension 700 in which a wheel 390 is suspended by an upper arm 710 and a lower arm 720 is used. The upper arm 710 is supported by a linear motor / slider (actuator, second rail) 615 provided in an annular shape along the center of the side surface of the vehicle body 100, and the lower arm 720 is provided in an annular shape along the lower portion of the side surface of the vehicle body 100. The slider (first rail) 670 is supported. A shock absorber 730 is interposed between the upper arm 710 and the lower arm 720.

Next, the operation will be described. In the eighth embodiment, since the double wishbone type suspension 700 is used, it is possible to more freely control the vehicle posture at the time of alignment change and acceleration / deceleration depending on the shape and arrangement of the arms. In addition, since the rigidity is high, steering stability is improved.
In addition to the effects (1) to (7) and (9) of the first embodiment, the geometry variable vehicle of the eighth embodiment has the following effects.

  (21) The suspension 700 is a double wishbone type suspension device, and the tread & wheelbase change actuator 350 is provided around the vehicle body, and is provided around the vehicle body with a slider 670 that supports the lower arm 720 of the suspension 700. A linear motor / slider 615 that supports the upper arm 710 of the suspension 700, and an actuator (linear motor / slider 615) that is provided between the upper arm 710 and the linear motor / slider 615 and relatively moves the vehicle body 100 and the suspension 700. And). As a result, it is possible to more freely control the alignment posture and the vehicle posture during acceleration / deceleration, and it is possible to improve the steering stability.

FIG. 24 is a side view showing a wheel mounting structure in the geometry variable vehicle of the ninth embodiment.
The ninth embodiment is an example in which a floating cabin type suspension frame (suspension device frame) 740 having a vibration isolating member (intermediate member) 750 interposed between the vehicle body 100 and the vehicle body 100 is used. The suspension frame 740 includes a slider (rail) 670 provided along the lower side of the vibration isolation member 750 and a linear motor slider (actuator, rail) provided annularly along the upper end of the vibration isolation member 750. 615 is supported to be rotatable relative to the vehicle body 100. The vibration isolation member 750 is fixed to the lower end portion of the vehicle body 100 via a coil spring (spring element) 760.
The other configuration is the same as that of the first embodiment shown in FIG.

  Next, the operation will be described. Since the floating cabin type suspension frame 740 is used in the ninth embodiment, the road surface input to the wheels 390 is absorbed by the coil spring 760, for example, when traveling on a rough road. For this reason, it is possible to suppress the input from the road surface from being transmitted to the vehicle body 100 side.

Next, the effect will be described.
In addition to the effects (1) to (7) and (9) of the first embodiment, the geometry variable vehicle of the ninth embodiment has the following effects.

  (22) The tread and wheelbase change actuator 350 is provided around the vehicle body, a suspension frame 740 that supports the suspension device (rod 620, bearing 630), a vibration isolation member 750 that is attached to the vehicle body via a coil spring 760, and the like. The slider 670 and the linear rail slider 615 that support the suspension frame 740 on the vibration isolation member 750, and the suspension frame 740 and the vibration isolation member 750 are provided between the vibration isolation member 750 and the suspension device. An actuator to be moved (linear rail slider 615). As a result, it is possible to provide a comfortable driving environment with good riding comfort.

FIG. 25 is a side view showing a wheel mounting structure in the geometry variable vehicle of the tenth embodiment.
The tenth embodiment differs from the ninth embodiment in that a slider 761 and a gear drive 770 are used instead of the linear rail slider 615 of the ninth embodiment as actuators for relatively moving the vibration isolating member 750 and the suspension device. .

The slider 761 is provided in an annular shape along the upper end of the side surface of the vibration isolation member 750. The gear drive 770 is provided on the suspension frame 740 and includes an electric motor 770a and a gear 770b.
Since other configurations are the same as those of the ninth embodiment, description thereof is omitted.

Next, the effect will be described.
In addition to the effects (1) to (7) of the first embodiment and the effect (22) of the ninth embodiment, the geometry variable vehicle of the tenth embodiment has the following effects.

  (23) Since the actuator includes the slider 761 provided in an annular shape on the vibration isolation member 750 and the gear drive 700 including the motor 770a and the gear 770b provided on the suspension frame 740, the vehicle body 100 and the suspension device Can be realized with a simple configuration.

FIG. 26 is a side view showing the wheel mounting structure in the geometry variable vehicle of the eleventh embodiment.
In the eleventh embodiment, the vehicle body side support end 600b of the suspension frame (suspension device frame) 600 corresponding to each wheel 390 is provided via a bearing 610 provided on the bottom surface of the vehicle body 100 (or the bottom surface of another suspension frame). Arranged at the four corners of 100.

In the eleventh embodiment, the expansion / contraction actuator (cylinder) 680 provided on the lower side of the vehicle body corresponds to the tread & wheelbase change actuator 350. The expansion / contraction of the rod of the expansion / contraction actuator 685 causes the suspension as shown in FIG. The frame 600 pivots around the attachment portion with the bearing 610 as a base point.
Since other configurations are the same as those in the first embodiment, the description thereof is omitted.

Next, the effect of Example 11 is demonstrated.
The geometry variable vehicle according to the eleventh embodiment has the following effects in addition to the effects (1) to (7) of the first embodiment.

  (24) The tread & wheelbase change actuator 350 includes a suspension frame 600 that supports the suspension device (rod 620, bearing 630, ball joint 640, suspension arm 650) and a wheel side support that supports the suspension device of the suspension frame 600. And a bearing 610 that rotatably supports the vehicle body side support end 600b opposite to the end 600a on the vehicle body 100. The bearings 610 are disposed at four corners of the vehicle body 100 for each wheel. Thereby, the wheel position changing mechanism that holds the suspension device movably to an arbitrary position on the track with respect to the vehicle body 100 can be realized with a simple configuration.

  (25) The tread & wheelbase change actuator 350 includes the telescopic actuator 685 that is connected to a position away from the vehicle body side support end 600b of the suspension frame 600 attached to the vehicle body 100. By doing so, a larger actuator can be used, and the responsiveness when changing the wheel position can be improved.

  The wheel mounting structure in the geometry variable vehicle of the twelfth embodiment is the same as that of the eighth embodiment shown in FIG. 23. However, in the twelfth embodiment, the slider (first rail) 670 and the linear motor slider (second rail) 615 are used. Have different orbits.

  As shown in FIG. 27, in Example 12, the track of the slider 670 is set in a circular shape. On the other hand, the track of the linear motor / slider 615 is set in a substantially square shape inscribed in a circle which is the track of the slider 670 at the reference position of each wheel 390 and bulged on the four sides. Thereby, the distance difference from the vehicle body center position of both tracks becomes maximum W in the vehicle longitudinal direction and maximum d in the vehicle width direction.

  Next, the operation will be described. In the twelfth embodiment, when the wheel 390 is moved from the reference position in the tread base reduction-wheel base extension direction or when the wheel 390 is moved in the tread base extension-wheel base reduction direction, the wheel 390 is the vehicle body. Since it moves upward with respect to 100, the center of gravity of the vehicle can be lowered. In other words, in the twelfth embodiment, by making the tracks of the linear motor slider 615 and the slider 670 different from each other, the vertical movement can be realized in addition to the variable tread base and wheel base due to the difference in the vertical track.

Next, the effect of Example 11 is demonstrated.
The geometry variable vehicle of the twelfth embodiment has the following effects in addition to the effects (1) to (7) and (9) of the first embodiment and the effect (21) of the eighth embodiment.

  (26) The tread & wheelbase change actuator 350 includes a linear motor slider 615 provided around the vehicle body and supporting the upper part of the suspension 700, and a slider 670 provided around the vehicle body and supporting the lower part of the suspension 700. The track of the linear motor slider 615 and the slider 670 is made different from each other. Thus, the vertical movement of the wheel 390 can be realized with a simple configuration.

(Other examples)
The best mode for carrying out the present invention has been described based on each embodiment, but the specific configuration of the present invention is not limited to each embodiment and does not depart from the gist of the invention. Any design changes are included in the present invention.

  For example, FIG. 28 is a diagram showing a wheel arrangement in the case where one drive wheel has failed and the other drive wheel has accelerated, and when one drive wheel has failed, the remaining drive wheel (normal drive wheel) Wheel) on the axle. For example, when the position of the remaining driving wheel is not changed, when driving force is generated by the remaining driving wheel, a yaw moment corresponding to the driving force is generated, and the handling performance of the vehicle is deteriorated.

  On the other hand, in the example of FIG. 28, when one of the drive wheels fails, the remaining drive wheels are rearranged on the axle line to prevent the generation of moment by the remaining drive wheels. Generation of yaw moment accompanying failure can be avoided, and stable running can be continued.

  FIG. 29 is a plan view showing another geometry variable vehicle, in which one drive wheel unit 300 is arranged at the front center position of the vehicle body 100, and one of the three steering wheel units 400 is connected to the vehicle body 100. This is a front-wheel drive vehicle that is disposed at the rear center position and the other two steered wheel units 400 are disposed on the left and right of the center of gravity of the vehicle body 100.

  FIG. 30 is a plan view showing another geometry variable vehicle, which is a three-wheel rear-wheel drive vehicle in which one steering wheel unit 400 is a front wheel and two drive wheels 300 are rear wheels. FIG. 31 is a plan view showing another geometry variable vehicle, which is a three-wheel front wheel drive vehicle in which one drive wheel unit 300 is a front wheel and two steered wheel units 400 are rear wheels.

For example, FIG. 32 (a) is an example in which each wheel position is changed so that the entrance / exit approaches the road surface in consideration of convenience when getting on / off.
When getting on and off, the steering actuator 340 is driven as shown in FIG. 32 (a) so that the direction of each wheel 390 is directed in the same direction as the wheel unit moving track 200, and then the tread & wheel base change actuator 350 is driven. Then, move each wheel 390 to the opposite side of the entrance 101. As a result, as shown in FIG. 32 (b), the entrance 101 can be brought as close to the road surface as possible, and a full flat boarding / exiting can be realized.

  Here, when each wheel position is changed, each wheel 390 is not moved simultaneously, but one wheel position is set as a base point, and wheel positions other than the base point are changed. At this time, by setting the direction of the wheel 390 as a base point to be different from the direction of the wheel unit moving track 200, the vehicle body 100 can be prevented from rotating.

As shown in FIG. 33, the shape of the trajectory on which the suspension device moves can be freely set such as (a) oval, (b) quadrangle, (c) rhombus, (d) triangle, and the like. Further, the wheel unit moving track 200 is not limited to an annular shape, and as shown in (e) and (f), a plurality of discontinuous tracks 200a, 200b, 200c having a length in consideration of the moving range of each wheel 390. May be set.
Moreover, you may perform control which combined multiple control shown to each Example.

1 is an external view illustrating a geometry variable vehicle according to a first embodiment. It is a top view which shows the geometry variable vehicle of Example 1. FIG. It is a side view which shows the wheel attachment structure in the geometry variable vehicle of Example 1. FIG. It is a figure which shows the tread base and the variable state of a wheel base in the geometry variable vehicle of Example 1. FIG. It is a figure which shows the cornering power with respect to the wheel load at the time of turning. It is a figure showing the position of the tread base in the case of equally distributing the wheel load of 4 wheels in the geometry variable vehicle of Example 1, and a wheel base. In vehicle with variable wheel geometry in Example 1 is a graph showing the movable range of l _1, l ₂ in the case where the height h of the center of gravity assuming 0.5 [m]. In the geometry variable vehicle of Example 2, it is a figure which shows the position of a tread base and a wheel base in the case of distributing the wheel load of 4 wheels arbitrarily. In the geometry variable vehicle of Example 3, it is a figure which shows the position of a tread base in the case of making the attitude angle of a vehicle into arbitrary attitude angles. In vehicle with variable wheel geometry in Example 4 is a graph representing a l _1, the movable range of l ₂ when moving the wheels other than the base point when any distribute wheel loads of the four wheels. It is a figure which shows the wheel arrangement | positioning at the time of acceleration of Example 4. FIG. It is a figure which shows the wheel arrangement | positioning at the time of the deceleration of Example 4. FIG. It is a figure which shows the wheel arrangement | positioning at the time of turning of Example 4. FIG. It is a figure which shows the wheel arrangement | positioning at the time of the deceleration turning of Example 4. FIG. It is a figure which shows the actuator load in the case of moving wheels other than the base point of Example 4. It is a figure which shows the movement track | orbit of the wheel in Example 5. FIG. It is a figure which shows the gravity center change by the movement of the wheel in Example 5. FIG. It is a figure which shows another center-of-gravity change by the movement of the wheel in Example 5. FIG. It is a figure which shows the example of the movement track | orbit of the wheel in Example 5. FIG. It is a figure which shows another example of the movement track | orbit of the wheel in Example 5. FIG. It is a side view which shows the wheel attachment structure in the geometry variable vehicle of Example 6. FIG. It is a side view which shows the wheel attachment structure in the geometry variable vehicle of Example 7. FIG. It is a side view which shows the wheel attachment structure in the geometry variable vehicle of Example 8. FIG. It is a side view which shows the wheel attachment structure in the geometry variable vehicle of Example 9. FIG. It is a side view which shows the wheel attachment structure in the geometry variable vehicle of Example 10. FIG. It is a side view which shows the wheel attachment structure in the geometry variable vehicle of Example 11. FIG. It is a figure which shows the wheel position control effect | action of Example 12. FIG. It is a figure which shows the wheel arrangement | positioning at the time of the drive wheel failure of Example 1. FIG. FIG. 6 is a diagram illustrating a modified example of the first embodiment. FIG. 6 is a diagram illustrating a modified example of the first embodiment. FIG. 6 is a diagram illustrating a modified example of the first embodiment. FIG. 6 is a diagram illustrating an operation example of the first embodiment. It is a figure which shows another Example.

Explanation of symbols

100 body
101 Boarding gate
110 Steering angle sensor
111 Accelerator position sensor
112 Brake sensor
120 Acceleration & Yaw Rate Sensor (Acceleration vector detection device)
200 wheel unit trajectory
200a orbit
300 Drive wheel unit
310 Wheel unit position sensor
320 Steering angle sensor
330 Drive actuator (drive device)
340 Steering actuator (steering mechanism)
350 Wheelbase change actuator (wheel position change mechanism)
390 wheels
400 Steering wheel unit
500 controller (wheel position control device)
600 Suspension frame (suspension device frame)
610 bearing
615 Linear motor slider (Linear slider, 2nd rail)
620 rod
630 bearings
640 Ball joint
650 suspension arm
660 steering gear
670 Slider (1st rail)
685 Telescopic actuator
690 shock absorber
700 suspension
710 Upper arm
720 Lower arm
730 Shock absorber
740 suspension frame
750 Anti-vibration member (intermediate member)
760 Coil spring (spring element)
770 gear drive

Claims (21)

A suspension device for suspending the wheels;
A steering mechanism provided in the suspension device for changing the direction of the wheel with respect to the vehicle body;
A driving device for driving the wheels;
A wheel position changing mechanism for holding the suspension device movably at an arbitrary position on the track with respect to the vehicle body;
A wheel position control device that outputs to the wheel position changing mechanism a movement command for changing the distance between the wheel in the acceleration direction and the position of the center of gravity in accordance with the direction of acceleration generated in the vehicle body center of gravity;
Equipped with a,
The wheel position changing mechanism includes a track for turning the suspension device in a horizontal direction around one place of the vehicle, and changes the tread base and the wheel base of the vehicle by changing the position of the wheel.
The wheel wheel movement trajectory of position changing mechanism, a wheel position changing vehicle, wherein the track der Rukoto pivoting movement in the horizontal direction all the wheels about the central position of the vehicle body. In the wheel position variable vehicle according to claim 1,
The wheel movement trajectory of the wheel position changing mechanism is a trajectory that turns all the wheels in the horizontal direction around the center position of the vehicle body without changing the distance between the center position and the wheel, and forms one annular trajectory. A geometry variable vehicle characterized by In the wheel position variable vehicle according to claim 1 or 2,
The wheel movement trajectory of the wheel position changing mechanism is a trajectory that causes all the wheels to turn in the horizontal direction around one place of the vehicle, and is a trajectory that displaces the wheels in the vertical direction of the vehicle along with the turning movement. A wheel position variable vehicle characterized by the above. In the wheel position variable vehicle according to claim 1 ,
The wheel position control device sets the distance in the acceleration direction from the wheel on the acceleration direction side to the gravity center position to be longer than the distance in the acceleration direction from the wheel on the opposite side to the acceleration direction to the gravity center position. A vehicle with variable wheel position. In the wheel position variable vehicle according to claim 1 ,
The wheel position control device changes a position of each wheel based on a target wheel load of each wheel calculated so that a wheel load of a driving wheel is larger than a wheel load of a steered wheel. Variable position vehicle. In the wheel position variable vehicle according to claim 1,
The wheel position control device changes the position of each wheel based on the target wheel load of each wheel calculated from the target vehicle attitude. In the wheel position variable vehicle according to claim 1,
An acceleration vector detection device for detecting the acceleration vector of the vehicle in the horizontal plane is provided,
The wheel position control device changes each wheel position on the basis of the direction of the detected acceleration vector as a reference. In the wheel position variable vehicle according to claim 7 ,
The wheel position control device bisects each wheel about a right axis of the acceleration vector, and changes each wheel position based on the right axis and the distance to each wheel. . In the wheel position variable vehicle according to claim 1,
The wheel position control device, when changing each wheel position, sets one wheel position as a base point and changes a wheel position other than the base point. In the wheel position variable vehicle according to claim 9,
The wheel position control device sets a wheel having a wheel load larger than that of a wheel whose wheel position is changed as a base point. In the wheel position variable vehicle according to claim 10 ,
The wheel position control device sets a wheel closest to the acceleration direction as a base point. In the wheel position variable vehicle according to claim 1 ,
The wheel position changing mechanism is
A suspension frame that supports the suspension;
A bearing that rotatably supports the vehicle body side support end opposite to the wheel side support end that supports the suspension device of the suspension device frame on the vehicle body;
An actuator provided between the suspension device or the suspension device frame and the vehicle body, and relatively moving the vehicle body and the suspension device;
A wheel position variable vehicle comprising: In the wheel position variable vehicle according to claim 1 ,
The wheel position changing mechanism is
A suspension frame that supports the suspension;
A rail provided around the vehicle body and supporting at least one of the suspension device and the suspension device frame on the vehicle body;
An actuator provided between the suspension device or the suspension device frame and the vehicle body, and relatively moving the vehicle body and the suspension device;
A wheel position variable vehicle comprising: In the wheel position variable vehicle according to claim 1,
The wheel position changing mechanism is
A suspension device frame that supports the suspension device and includes a tiltable portion that is tiltable in the vehicle vertical direction according to the force from the road surface input to the wheel,
A bearing that rotatably supports the vehicle body side support end opposite to the wheel side support end that supports the suspension device of the suspension device frame on the vehicle body;
A rail provided around the vehicle body and supporting at least one of the suspension device and the suspension device frame on the vehicle body;
An actuator provided between the suspension device or the suspension device frame and the vehicle body, and relatively moving the vehicle body and the suspension device;
A wheel position variable vehicle, comprising: a shock absorber disposed between the suspension device and a vehicle body. In the wheel position variable vehicle according to claim 1,
The suspension device is a double wishbone type suspension device,
The wheel position changing mechanism is
A first rail provided around the vehicle body and supporting a lower arm of the suspension device;
A second rail provided around the vehicle body and supporting an upper arm of the suspension device;
An actuator provided between the lower arm and the first rail or between the upper arm and the second rail, and relatively moving the vehicle body and the suspension device;
A wheel position variable vehicle comprising: In the wheel position variable vehicle according to claim 1,
The wheel position changing mechanism is
A suspension frame that supports the suspension;
An intermediate member attached to the vehicle body via a spring element;
A rail provided around the vehicle body and supporting the suspension device or the suspension device frame on an intermediate member;
An actuator that is provided between the suspension device or the suspension device frame and the intermediate member and moves the intermediate member and the suspension device relatively;
A wheel position variable vehicle comprising: The wheel position variable vehicle according to any one of claims 12 to 16 ,
The wheel position variable vehicle according to claim 1, wherein the actuator is a linear slider provided annularly on a vehicle body or an intermediate member. The wheel position variable vehicle according to any one of claims 12 to 16 ,
The wheel position variable vehicle, wherein the actuator comprises a slider provided in a ring shape on a vehicle body or an intermediate member, and a gear drive including a motor and a gear provided on a suspension device or a suspension device frame. In the wheel position variable vehicle according to claim 1 ,
The wheel position changing mechanism is
A suspension frame for supporting the suspension;
A bearing that rotatably supports the vehicle body side support end opposite to the wheel side support end that supports the suspension device of the suspension device frame on the vehicle body;
With
The wheel position variable vehicle, wherein the bearings are arranged at four corners of the vehicle body for each wheel. In the wheel position variable vehicle according to claim 19 ,
The wheel position changing mechanism includes a telescopic actuator connected to a position away from a vehicle body side support end of a suspension device frame attached to a vehicle body. In the wheel position variable vehicle according to claim 1,
The wheel position changing mechanism is
A first rail provided around the vehicle body and supporting a lower portion of the suspension device;
A second rail provided around the vehicle body and supporting an upper portion of the suspension device;
With
The wheel position variable vehicle, wherein the first rail and the second rail have different tracks.

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